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Local Extinction

In 1997 the Jasper Ridge population of the bay checkerspot declined to extinction [1]. The discovery of the large population near Morgan Hill in the mid-1980's made Ehrlich, Murphy, and colleagues believe that they could learn more from watching the Jasper Ridge population decline to extinction than by intervening to prevent its extinction.

In a similar vein, populations of a different subspecies of Euphydryas editha underwent a drastic change in the central Sierra Nevada [3]. Clearcutting of the forest in part of Sequoia National Forest in 1967 created artificial meadows that were excellent habitat, and the butterflies switched to a different food plant that was very abundant there, Collinsia torreyi.


next up previous
Next: Conclusions Up: Population Viability Analysis Bay Previous: Metapopulation Dynamics
Kent Holsinger 2013-09-15